+Kostya (code owner for LLVM sanitizer_common) as FYI On Wed, Oct 2, 2019 at 12:54 AM Eric W. Biederman <ebiederm@xxxxxxxxxxxx> wrote: > Kees Cook <keescook@xxxxxxxxxxxx> writes: > > On Tue, Oct 01, 2019 at 01:36:32PM -0500, Eric W. Biederman wrote: [...] > > I think you can actually take this further and remove (or at least > > empty) the uapi/linux/sysctl.h file too. [...] > I would make it a followup that removes uapi/linux/sysctl.h. I don't > see anything in it that isn't about the sysctl system call. I will keep > it a separate patch as I can imagine something silly that needs the > header file to compile. A separate patch would make a revert easier > if we find something like that. Unfortunately, I think that header (or at least parts of it) has to stay around for now: Looking through the search results for linux/sysctl.h (ignoring glibc's sys/sysctl.h, which pulls in linux/sysctl.h, because almost all of those hits are conditional includes for BSD systems) on codesearch.debian.net, I noticed that e.g. the ASAN code that GCC and LLVM use pulls in linux/sysctl.h and uses things from it: https://github.com/llvm-mirror/compiler-rt/blob/124fd5d9aff57cf47bf077df81ad939b289acc6e/lib/sanitizer_common/sanitizer_platform_limits_posix.cpp#L1063 And indeed, after replacing /usr/include/linux/sysctl.h with an empty file, a build of LLVM's runtime library component (compiler-rt) (git HEAD version) falls over with error spew about __sysctl_args: ==================== $ cmake -G Ninja -DCMAKE_BUILD_TYPE=Release -DLLVM_ENABLE_PROJECTS='clang;compiler-rt' -DCMAKE_C_COMPILER=clang-7 -DCMAKE_CXX_COMPILER=clang++-7 -DLLVM_TARGETS_TO_BUILD="X86" -DLLVM_USE_LINKER=lld-7 -DBUILD_SHARED_LIBS=Off ../llvm [...] $ ninja -j64 FAILED: projects/compiler-rt/lib/sanitizer_common/CMakeFiles/RTSanitizerCommonNoTermination.i386.dir/sanitizer_platform_limits_posix.cpp.o [...] [...]/compiler-rt/lib/sanitizer_common/sanitizer_platform_limits_posix.cpp:1063:17: error: use of undeclared identifier '__sysctl_args' CHECK_TYPE_SIZE(__sysctl_args); ^ [...]/compiler-rt/lib/sanitizer_common/sanitizer_platform_limits_posix.cpp:1064:23: error: use of undeclared identifier '__sysctl_args' CHECK_SIZE_AND_OFFSET(__sysctl_args, name); ^ [...]/compiler-rt/lib/sanitizer_common/sanitizer_platform_limits_posix.cpp:1064:1: error: expected expression CHECK_SIZE_AND_OFFSET(__sysctl_args, name); ^ [...]/compiler-rt/lib/sanitizer_common/sanitizer_platform_limits_posix.h:1438:34: note: expanded from macro 'CHECK_SIZE_AND_OFFSET' sizeof(((CLASS *)NULL)->MEMBER)); \ ^ [...]/compiler-rt/lib/sanitizer_common/sanitizer_platform_limits_posix.cpp:1064:23: error: unknown type name '__sysctl_args' CHECK_SIZE_AND_OFFSET(__sysctl_args, name); ^ ====================
